Sewing machine



FIG. 1 is a top plan view of a sewing machine;

FIG. 2 is a front view of the sewing machine;

FIG. 3 is a left side view of the sewing machine;

FIG. 4 is a right side view of the sewing machine;

FIG. 5 is a rear view of the sewing machine; and,

FIG. 6 is a perspective view of the sewing machine.

The broken lines which define the bounds of the claimed design form no part thereof. 

The ornamental design for a sewing machine, as shown and described. 